ISIS: Refactor area to include AFI

bio-routing · Jul 29, 2024 · 3440ac9 · 3440ac9
1 parent d55ba43
commit 3440ac9
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Showing 6 changed files with 99 additions and 22 deletions.
diff --git a/protocols/isis/server/hello_sender.go b/protocols/isis/server/hello_sender.go
@@ -87,7 +87,7 @@ func (nifa *netIfa) p2pHello() *packet.P2PHello {
 
 	areas := make([]types.AreaID, 0)
 	for _, net := range nifa.srv.nets {
-		areas = append(areas, append([]byte{net.AFI}, net.AreaID...))
+		areas = append(areas, net.AreaID)
 	}
 	h.TLVs = append(h.TLVs, packet.NewAreaAddressesTLV(areas))
 

diff --git a/protocols/isis/server/neighbor_manager.go b/protocols/isis/server/neighbor_manager.go
@@ -186,7 +186,7 @@ func (nm *neighborManager) validateP2PHello(hello *packet.P2PHello) error {
 func (nifa *netIfa) validateAreasL1(receivedAreas []types.AreaID) bool {
 	localAreas := make([]types.AreaID, 0)
 	for _, net := range nifa.srv.nets {
-		localAreas = append(localAreas, append([]byte{net.AFI}, net.AreaID...))
+		localAreas = append(localAreas, net.AreaID)
 	}
 
 	for _, needle := range receivedAreas {

diff --git a/protocols/isis/server/neighbor_manager_test.go b/protocols/isis/server/neighbor_manager_test.go
@@ -22,8 +22,7 @@ func TestValidateAreasL1(t *testing.T) {
 				srv: &Server{
 					nets: []*types.NET{
 						{
-							AFI:    0x49,
-							AreaID: []byte{1},
+							AreaID: []byte{0x49, 1},
 						},
 					},
 				},
@@ -41,12 +40,10 @@ func TestValidateAreasL1(t *testing.T) {
 				srv: &Server{
 					nets: []*types.NET{
 						{
-							AFI:    0x49,
-							AreaID: []byte{1},
+							AreaID: []byte{0x49},
 						},
 						{
-							AFI:    0x49,
-							AreaID: []byte{0xff},
+							AreaID: []byte{0x49, 0xff},
 						},
 					},
 				},
@@ -64,12 +61,10 @@ func TestValidateAreasL1(t *testing.T) {
 				srv: &Server{
 					nets: []*types.NET{
 						{
-							AFI:    0x49,
-							AreaID: []byte{1},
+							AreaID: []byte{0x49, 1},
 						},
 						{
-							AFI:    0x49,
-							AreaID: []byte{0xff},
+							AreaID: []byte{0x49, 0xff},
 						},
 					},
 				},

diff --git a/protocols/isis/types/net.go b/protocols/isis/types/net.go
@@ -9,7 +9,6 @@ const (
 
 // NET represents an ISO network entity title
 type NET struct {
-	AFI      byte
 	AreaID   AreaID
 	SystemID SystemID
 	SEL      byte
@@ -29,8 +28,8 @@ func ParseNET(addr []byte) (*NET, error) {
 
 	areaID := []byte{}
 
-	for i := 0; i < addrLen-systemIDLen-2; i++ { // -2 for SEL and "off by one"
-		areaID = append(areaID, addr[i+1])
+	for i := 0; i < addrLen-systemIDLen-1; i++ {
+		areaID = append(areaID, addr[i])
 	}
 
 	systemID := SystemID{
@@ -43,7 +42,6 @@ func ParseNET(addr []byte) (*NET, error) {
 	}
 
 	return &NET{
-		AFI:      addr[0],
 		AreaID:   areaID,
 		SystemID: systemID,
 		SEL:      addr[addrLen-1],

diff --git a/protocols/isis/types/net_test.go b/protocols/isis/types/net_test.go
@@ -0,0 +1,85 @@
+package types
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestParseNET(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    []byte
+		expected *NET
+		wantFail bool
+	}{
+		{
+			name: "Simple long valid NET",
+			input: []byte{
+				0x49, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // Area (including AFI)
+				0x01, 0x00, 0x00, 0x00, 0x00, 0x01, // SysID
+				0x00, // SEL
+			},
+			expected: &NET{
+				AreaID: []byte{
+					0x49, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+				},
+				SystemID: SystemID{
+					0x01, 0x00, 0x00, 0x00, 0x00, 0x01,
+				},
+				SEL: 0x00,
+			},
+		},
+		{
+			name: "Simple short valid NET",
+			input: []byte{
+				0x49,                               // Area (including AFI)
+				0x01, 0x00, 0x00, 0x00, 0x00, 0x01, // SysID
+				0x00, // SEL
+			},
+			expected: &NET{
+				AreaID: []byte{
+					0x49,
+				},
+				SystemID: SystemID{
+					0x01, 0x00, 0x00, 0x00, 0x00, 0x01,
+				},
+				SEL: 0x00,
+			},
+		},
+		{
+			name: "Too long NET",
+			input: []byte{
+				0x49, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, // Area (including AFI)
+				0x01, 0x00, 0x00, 0x00, 0x00, 0x01, // SysID
+				0x00, // SEL
+			},
+			wantFail: true,
+		},
+		{
+			name: "Too short NET",
+			input: []byte{
+				0x01, 0x00, 0x00, 0x00, 0x00, 0x01, // SysID
+				0x00, // SEL
+			},
+			wantFail: true,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			n, err := ParseNET([]byte(test.input))
+			if err != nil && !test.wantFail {
+				t.Errorf("unexpected failure for test %q: %v", test.name, err)
+				return
+			}
+
+			if err == nil && test.wantFail {
+				t.Errorf("unexpected success for test %q", test.name)
+				return
+			}
+
+			assert.Equal(t, test.expected, n, test.name)
+		})
+	}
+}
diff --git a/tests/isis_integration_test.go b/tests/isis_integration_test.go
@@ -229,16 +229,16 @@ var (
 		0,    // Reserved
 		0,    // Max. Area addresses
 		// LSP
-		0, 0x5f, // Length
+		0, 0x60, // Length
 		7, 6, // Remaining Lifetime
 		12, 12, 12, 13, 13, 13, 0, 0, // LSP ID
 		0, 0, 0, 3, // Sequence number
-		0x52, 0xca, // Checksum
+		0x58, 0x79, // Checksum
 		0, // Type block
 		// TLVs
 		1, // Area
-		2, // Length
-		1, 0,
+		3, // Length
+		2, 0x49, 0,
 		129,      // Protocols Supported
 		2,        // Length
 		204, 142, // IPv4 + IPv6
@@ -294,8 +294,7 @@ func TestISISServer(t *testing.T) {
 	du := &device.MockServer{}
 	s, err := server.New([]*types.NET{
 		{
-			AFI:      0x49,
-			AreaID:   types.AreaID{0x00},
+			AreaID:   types.AreaID{0x49, 0x00},
 			SystemID: types.SystemID{12, 12, 12, 13, 13, 13},
 			SEL:      0x00,
 		},